1. Field of the Invention
The present invention relates to a ruler. More particularly, the present invention relates to a ruler for measuring and marking lengths and angles relative to a horizontal plane by utilizing gravity.
2. Description of the Prior Art
Numerous innovations for measuring devices have been provided in the prior art that will be described. Even though these innovations may be suitable for the specific individual purposes to which they address, however, they differ from the present invention.
FOR EXAMPLE, U.S. Pat. No. 4,267,642 to Stapleford teaches an angle gage mechanism for use in measuring angles of surfaces in a work piece usually requiring more than one conventional tool at the present time. This invention is capable of performing the most used functions of at least five conventional tools, to wit, solid square, bevel protractor, combination square, rule and bevel. It also includes a vernier for added accuracy and a plurality of pre-set angles that can be readily selected by the user.
The invention comprises a frame with a cylindrical hole housing a cylindrical spindle having means for readily locking the spindle at predetermined angles with respect to the frame and means for frictionally locking the spindle at any angle with respect to the frame. A slot in the frame aligned with a partial slot in the spindle receive a slidable ruler. The frame is further provided with means for frictionally locking the ruler relative to the spindle.
ANOTHER EXAMPLE, U.S. Pat. No. 4,715,127 to Bernabeu teaches a device for measuring angles between an oriented axis and a vector that is provided in the form of a flat plate of transparent material having at least two straight parallel edges and an arrow situated on the plate and parallel with the edges; the plate has a number of zones marked on the surface thereof and a closed curve centrally located and a longitudinal line provided parallel to the edges on either side of the central zone. Markings are provided in the zones to facilitate the measurement of the angles without requiring removal of the plate from the surface on which the angles are being measured.
FINALLY, STILL ANOTHER EXAMPLE, U.S. Pat. No. 5,383,276 to Izumi teaches an angle trisecting device with a base section having two angle indicating scales and an elongated member with a straight edge portion. The elongated member is pivotally mounted on the base section. A given angle on one angle indicating scale coinciding with the straight edge portion corresponds to a trisected angle on the other angle indicating scale coinciding with the straight edge portion. Pivot pins extend from the elongated member and are removably captured in respective base slots to ensure reliable operation. In another embodiment a guide wall extends from the base to ensure reliable operation. An optional link arm is pivotally mounted to the base section and with one end pivotally mounted to the elongated member.
It is apparent that numerous innovations for measuring devices have been provided in the prior art that are adapted to be used. Furthermore, even though these innovations may be suitable for the specific individual purposes to which they address, however, they would not be suitable for the purposes of the present invention as heretofore described.